1. Field of the Invention
The present invention relates to a digital television receiver and method of controlling an antenna of the same, and more particularly, to an antenna controller of a digital television receiver and a controlling method thereof.
2. Background of the Related Art
VSB (Vestigial Side Band) has been chosen as a standard form for transmitting a terrestrial microwave channel in digital television broadcasting. Thus, concepts and ideas have been made to propose the early-stage antennas for a VSB receiver, and ATSC prepares the standardization of the VSB antennas. Yet, no antenna applied to a digital television receiver has been introduced in public, and further has been commercialized.
Generally, antennas able to be used for digital television receivers are mainly divided into two categories.
First, there is a general outdoor antenna having a benefit of high receive performance but having defects such as large size and installment inconvenience.
Second, there is an indoor antennal having benefits of small size and installment convenience but defects such that a viewer has to adjust a direction of the antenna by monitoring a screen in direct when a receive sensitivity is reduced.
Besides, a plurality of multi-paths and frequency obstacles have a chance to exist in the terrestrial channels in the digital television broadcasting. Therefore, receive characteristics of an antenna of a digital television receiver may have a great influence on the entire characteristics of the digital television receiver. Other antennas and their problems depending on their environments are described as follows by referring to FIG. 1 to FIG. 3.
FIG. 1 to FIG. 3 show diagrams of a no-directional antenna, a directional antenna, and a smart antenna, respectively.
First, a television receiver using a non-directional antenna in FIG. 1 enables to receive the major signal from all directions only through the channels where intensity of the main signal is strong while signals in multi-paths are weak. Yet, the television receiver in FIG. 1 fails to easily receive the wanted channel in the channels where the main signal is weak and the signals in the multi-paths are strong through indoor antennas, downtown-building-area antennas and the like, thereby reducing the performance of the digital television receiver.
Second, a direction antenna in FIG. 2 may be used in order to overcome the defects of the non-directional antenna. Yet, the main signal may be blocked by the moving obstacles against radio waves under the circumstance that states of the channels vary severely. In this case, it is difficult for the antenna to receive the main signal from other directions, whereby the performance of the digital television receiver is reduced as well. As mentioned in the foregoing explanation, the non-directional antenna has a trade-off relation with the directional antenna.
Third, a smart antenna in FIG. 3 may be considered as a solution so as to solve the problems of the non-directional and directional antennas. The above defects/problems may be settled by making use of the smart antenna on the assumption of the existence of a control system.